Jacobi

Jacobi’s multiple researches into Ashkenazi families, many of
them going back several centuries, involve tens of thousands of individuals,
whose precise dates of birth and death were not always known. In order to situate
these people accurately in time, Jacobi devised a unique system, called an “Absolute
Generations Scale”, which he applied to all the individuals recorded in his Monographs.
This allowed him to position them in their correct generational order, to
synchronize them with their own and other kinship groups appearing on diverse
family trees, and, from a broader perspective, to place them within wider time-frames
of reference, both historical and societal.

The scale of numbered generations begins with the present-day
and covers the whole of the Middle Ages, for example to the eminent Jewish
scholar, Rashi (1040-1105). Ultimately it can be extended back to King David
(ca. 1,000 BCE) and well beyond. It is of great use to genealogists generally,
confronted with challenge of placing individuals accurately on a standardised
generational time-scale.

Click here for a detailed article by Dr. Chanan Rappaport on the Jacobi “Absolute Generations Scale”.